The present invention relates to methods and compositions for imparting stain resistance to a substrate. Substrates that may be treated with the methods and compositions of the invention preferably include fibers containing free amino groups, including, but not limited to, polyamide fibers. The processes and compositions of the invention provide the substrate with stain resistance and good photo stability, which prevents yellowing.
Materials and substrates containing free amino groups are subject to stain by certain natural and artificial colorants found in foods and other consumer products. The addition of stain resistant characteristics to substrates containing free amino groups provides a more desirable end product for the consumer.
Substrates, including fibers containing free amino groups, such as polyamide fibers, can be made stain resistant to certain stains by contacting the substrate with a solution containing an anionically modified phenol formaldehyde polymer, phenol sulfonates and their derivatives, naphthalene condensates, or blends of these materials. It is also known to blend these materials with polyether polymers, vinyls, polycarbonate polymers, and ethylene polymers.
One method of imparting stain resistance to fibers containing free amino groups is disclosed in U.S. Pat. No. 4,699,812 (Munk et al.). U.S. Pat. No. 4,699,812 discloses a process for imparting stain resistance in which a solution of aliphatic sulfonic acid is applied to the fibers, which are then dried.
U.S. Pat. No. 4,592,940 (Blyth et al.) discloses a process for imparting stain resistance to nylon fibers, in which the fibers are treated with the condensation products of formaldehyde and a mixture of diphenolsulfone and phenolsulfonic acid. The substrate is treated by immersing the carpet in the boiling treatment solution at a pH of 4.5 or less.
U.S. Pat. No. 4,822,373 (Olson et al.) discloses a process for treating polyamide materials in which a fibrous polyamide substrate is treated with a combination of (a) a partially sulfonated phenol formaldehyde polymer and (b) polymethacrylic acid, copolymers of methacrylic acid, or combinations of polymethacrylic acid and copolymers of methacrylic acid. The solution is generally applied as an aqueous solution at a pH below about 7.
U.S. Pat. No. 4,940,757 (Moss, III et al.) discloses a stain resistant polymeric composition for fibers having polyamide linkages. The composition is prepared by polymerizing an xcex1-substituted acrylic acid in the presence of a sulfonated aromatic condensation polymer. The composition is applied to the substrate via flood, spray, foam methods, etc.
Additionally, U.S. Pat. No. 3,949,124 (Jilla) discloses a method and composition of imparting soil-repellency and antistatic properties. The reference discloses the pretreatment of a substrate with a material containing the condensation products of formaldehyde and another component chosen from a wide variety and long list, some of which are sulfonated phenol, diaryl sulfone, urea, melamine and dicayndiamide, followed by heat treatment and application of a separate composition containing, as one ingredient, a water-dispersible polyester and amino polymer followed by another heat treatment. U.S. Pat. No. 3,949,124 concerns imparting antistatic and antisoiling properties, which are distinct from stain resistance.
Those skilled in the art recognize that while anionically modified phenol formaldehyde polymers, napthalene condensates, lignin sulfonates and phenol sulfonate derivatives provide stainblocking, their photo instability causes yellowing of the dyed substrate over time. Therefore, there exists a need for compositions and methods that provide excellent stain resistance, while at the same time exhibiting reduced photo instability, i.e. reduced yellowing.
The present invention solves these problems, and provides further surprising properties. These and further objects of the invention will be more readily appreciated when considering the following disclosure and appended claims.
The present invention concerns a composition for imparting stain resistance to a substrate comprising (a) a component selected from the group consisting of (1) an anionically modified phenol formaldehyde polymer comprising a phenol moiety and a formaldehyde moiety, (2) a naphthalene condensate, (3) a lignin sulfonate, (4) a phenol sulfonate derivative, a mixture thereof, and (5) a (meth)acrylic polymer comprising residues of acrylic or methacrylic acid; and (b) a polyester.
The invention further concerns a method of treating a substrate for stain resistance comprising applying to the substrate an aqueous solution or dispersion comprising (a) a component selected from the group consisting of (1) an anionically modified phenol formaldehyde polymer comprising a phenol moiety and a formaldehyde moiety, (2) a naphthalene condensate, (3) a lignin sulfonate, (4) a phenol sulfonate derivative, a mixture thereof, and (5) a (meth)acrylic polymer comprising residues of acrylic or methacrylic acid; (b) a polyester; and (c) water.
The invention further concerns a method of treating a substrate for stain resistance comprising treating the substrate with a stain resist composition comprising (a) a component selected from the group consisting of (1) an anionically modified phenol formaldehyde polymer comprising a phenol moiety and a formaldehyde moiety, (2) a naphthalene condensate, (3) a lignin sulfonate, (4) a phenol sulfonate derivative, a mixture thereof, and (5) a (meth)acrylic polymer comprising residues of acrylic of methacrylic acid; and (b) a polyester.
The invention also includes articles treated with the composition, and articles made using treated substrates. In a preferred embodiment, the articles include, but are not limited to, fibers having polyamide groups.
The present invention may be understood more readily by reference to the following detailed description of preferred embodiments of the invention and the Examples included therein.
Before the present compositions of matter and methods are disclosed and described, it is to be understood that this invention is not limited to specific synthetic methods or to particular formulations, as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.
In this specification and in the claims which follow, reference will be made to a number of terms which shall be defined to have the following meanings:
The singular forms xe2x80x9ca,xe2x80x9d xe2x80x9canxe2x80x9d and xe2x80x9cthexe2x80x9d include plural referents unless the context clearly dictates otherwise.
xe2x80x9cOptionalxe2x80x9d or xe2x80x9coptionallyxe2x80x9d means that the subsequently described event or circumstances may or may not occur, and that the description included instances where said event or circumstance occurs and instances where it does not.
xe2x80x9cTotal weightxe2x80x9d, when used in reference to the stain resist composition, means the weight of the stain resist composition including components (a), (b) and any other components present in the stain resist composition.
Throughout this application, where publications are referenced, the disclosures of these publications in their entireties are hereby incorporated by reference into this application in order to more fully describe the state of the art to which this invention pertains.
The present invention concerns a composition for imparting stain resistance to a substrate comprising (a) a component selected from the group consisting of (1) an anionically modified phenol formaldehyde polymer comprising a phenol moiety and a formaldehyde moiety, (2) a naphthalene condensate, (3) a lignin sulfonate, (4) a phenol sulfonate derivative, a mixture thereof, and (5) a (meth)acrylic polymer comprising residues of acrylic or methacrylic acid; and (b) a polyester.
The invention further concerns a method of treating a substrate for stain resistance comprising applying to the substrate an aqueous solution or dispersion comprising (a) a component selected from the group consisting of (1) an anionically modified phenol formaldehyde polymer comprising a phenol moiety and a formaldehyde moiety, (2) a naphthalene condensate, (3) a lignin sulfonate, (4) a phenol sulfonate derivative, a mixture thereof, and (5) a (meth)acrylic polymer comprising residues of acrylic or methacrylic acid; (b) a polyester; and (c) water.
xe2x80x9cA mixture thereofxe2x80x9d as used herein in reference to component (a) means a mixture of one or more of components (1) through (4).
The invention further concerns a method of treating a substrate for stain resistance comprising treating the substrate with a stain resist composition comprising (a) a component selected from the group consisting of (1) an anionically modified phenol formaldehyde polymer comprising a phenol moiety and a formaldehyde moiety, (2) a naphthalene condensate, (3) a lignin sulfonate, (4) a phenol sulfonate derivative, a mixture thereof, and (5) a (meth)acrylic polymer comprising residues of acrylic of methacrylic acid; and (b) a polyester.
The invention also includes articles treated with the composition. In a preferred embodiment, the articles include, but are not limited to, fibers having polyamide groups.
xe2x80x9cStain resistancexe2x80x9d may be quantitatively determined based on the AATCC Test Method 175-1993. Many production facilities, however, have modified this test to meet their own specific production requirements. The stain resistance may vary according to the end use of the substrate. In most uses, the substrate should have a stain resistance of at least 4 based on the AATCC Test Method, preferably at least 6, more preferably at least 7, and even more preferably 8 or higher, all based on the AATCC Test Method.
Those skilled in the art recognize that while anionically modified phenol formaldehyde polymers, napthalene condensates, lignin sulfonates and phenol sulfonate derivatives provide excellent stainblocking, their photo instability causes yellowing of the dyed substrate. The applicants have unexpectedly discovered that the combination of hydrophobic dispersible and/or water soluble polyester polymers and an anionically modified phenol formaldehyde polymer, naphthalene condensate, lignin sulfonate, phenol sulfonate derivative, or (meth)acrylic polymer, eliminates or substantially reduces the photo instability that causes the yellowing of the dyed substrate. Combining the anionically modified phenol formaldehyde polymers, naphthalene condensate, lignin sulfonate, phenol sulfonate derivate or methacrylic polymer having stain resist imparting properties, and a polyester, both hydrophobic dispersible and/or water soluble, produces a heretofore unrecognized synergistic effect.
The substrates treated with the compositions of the invention preferably include, but are not limited to, polyamide fibers or other synthetic fibers containing free amino groups, or the materials used to form the substrate or fibers. Fibers containing free amino groups may be obtained by a variety of methods, including but not limited to, the condensation reaction of hexamethylenediamine with adipic acid, hexamethylenediamine with sebacic acid, w-aminodecanoic acid, caprolactam and dodecylcaprolactam. Fibers formed from polyaryl amides, including type 6 and type 6.6 nylons, may be treated by the composition and method of this invention.
The treated fibers may be twisted, woven, tufted and sewn into various forms of textile materials including, but not limited to, rugs, carpets, and yarns. The fibers may be treated and then formed into the various forms of textile materials, or the formed textile may be treated.
The anionically modified phenol formaldehyde polymers appropriate for use in this invention include, but are not limited to, condensation products of aldehydes with phenyl bearing molecules and anionically modifying agents. The phenol formaldehyde polymer may be anionically modified by methods including, but not limited to, sulfonation, phosphonation and acylation. Sulfonation is preferred and is preferably accomplished using sulfonic acid. In one embodiment, the polymer contains phenylsulfonic acid residues. In other embodiments, the polymer may be a condensation product of naphtholsulfonic acid and an aldehyde, an anionically modified hydroxyaromatic formaldehyde condensate, the condensation product of anionically modified dihydroxydiphenylsulfone or the condensation product of naphtholsulfonic acid or the derivatives of any of these polymers.
Examples of other suitable anionically modified phenol formaldehyde polymers or compounded materials based on phenol formaldehyde polymers include, but are not limited to, FX 369, 668, 661 (3M), INTRATEX N (Crompton and Knowles), ERIONYL PA (Ciba-Geigy), NYLOFIXAN P and PM (formerly Sandoz, now Claraint), MESITOL NBS (formerly Mobay Chemical Corp., now Dystar, Inc.), ARROTEX 2035, 2077 (Arrow Engineering), CB-130 (Grifftex Corp.), etc. In an alternative embodiment, lignin sulfonates may be used in place of the anionically modified phenol formaldehdye polymer. In yet another embodiment, naphthalene condensates may be used in place of the anionically modified phenol formaldehyde polymer. In yet another embodiment, phenol sulphonate derivatives may be used in place of the anionically modified phenol formaldehyde polymer.
Compounds which are suitable for use as component (a) in this invention are disclosed in U.S. Pat. Nos. 4,592,940; 4,839,212; 4,822,373; 4,940,757; and EP 332342 A, equivalent to U.S. Pat. No.4,937,123, which are herein incorporated by this reference in their entirety and for the teachings of suitable anionically modified phenol formaldehyde polymers. Sulfonated phenol formaldehyde polymer is the preferred anionically modified phenol formaldehyde polymer.
Dispersible and/or water soluble polyesters may be used in the invention. One suitable polyester for use in the composition is EVCOTE WR-2, disclosed in U.S. Pat. No. 4,977,191, a dispersible and or water soluble polyester product from EvCo Corporation.
The term xe2x80x9cpolyester,xe2x80x9d as used herein, refers to any unit-type of polyester falling within the scope of the polyester portion of the blend, including but not limited to homopolyesters, copolyesters (two or more types of acid or glycol residues of monomeric units) and terpolyesters. The polyesters of the present invention comprise an acid residue and a glycol residue. The acid residues of the polyesters of the present invention total 100 mol % and the glycol residues of the polyesters of the present invention total 100 mol %.
In one embodiment, water soluble or dispersible terephthalate based polyesters or copolyesters are used in the composition for imparting stain resistance. The terephthalate based polyester or copolyester may be recycled, as disclosed in U.S. Pat. No. 4,977,191, or virgin terephthalate polymers may be used. It is preferred that the acid residues of the copolyester comprise residues of terephthalic acid.
In another embodiment, a mixture of water dispersible and water soluble polyesters is present in the composition. Preferably, the water soluble and water dispersible polyesters comprise residues of terephthalic acid. The water dispersible polyester may be provided in the form of an emulsion.
The diol component of the polyester may comprise residues of a wide variety of diols, including, but not limited to, residues of ethylene glycol, diethylene glycol, triethylene glycol, cyclohexanedimethanol, propylene glycol, butylene glycol, neopentyl glycol, 1,5-pentanediol, 1,6 hexanediol or mixtures thereof The polyester preferably comprises residues of diethylene glycol, neopentyl glycol or mixtures thereof.
The polyester may comprise residues of polyoxyalkylene glycols derived from any polyol having three or more alcohol functions, including but not limited to glycerol, trimethylolpropane, pentaerythritol, erythritol, sorbitol, mannitol, other sugar alcohols or monosaccharides. The polyols can be oxyalkylated with an alkylene oxide, including, but not limited to, ethylene oxide, propylene oxide or a mixture thereof.
References proposing the use of polyesters containing terephthalate units and units derived from alkylene and polyoxyalkylene glycols for fiber or fabric treatment which are suitable for use in this invention include U.S. Pat. Nos. 3,959,230; 3,962,152; 4,027,346; 4,125,370; and U.S. Pat. No. 4,370,143.
The stain resist compositions of this invention comprise from 1% to 99% by weight of the stain resist composition, based on the total weight of the stain resist composition, of the anionically modified phenol formaldehyde polymer, naphthalene condensate, lignin sulphonate or phenol sulphonate derivative and from 1% to 99% of the polyester by weight of the stain resist composition, based on the total weight of the stain resist composition. Preferably, the stain resist composition contains an anionically modified phenol formaldehyde polymer, naphthalene condensate, lignin sulfonate or phenol sulphonate derivative at from 5% to 30% by weight of the total stain resist composition and a dispersible polyester varying at from 1% to 95% by weight of the total stain resist composition. More preferably, the polyester is a water dispersible polyester present at from 1 to 50% by weight of the total stain resist composition.
In another embodiment, another polymeric material comprising (meth)acrylic polymers, the (meth)acrylic polymers comprising residues of acrylic and/or methacrylic acid, may be used instead of the above-mentioned anionically modified phenol formaldehyde polymer, naphthalene condensate, lignin sulphonate etc. as component (a). It is preferred that component (a) comprise (meth)acrylic polymers. Preferably the (meth)acrylic polymer has a molecular weight of 1,500 to 30,000. It is further preferred that the (meth)acrylic polymer comprise methacrylic units, more preferably a homopolymer of methacrylic acid residues and having a preferable molecular weight of 1,500 to 30,000, more preferably 7,000 to 25,000, even more preferably 10,000 to 20,000. The combination of the polyester and acrylic/methacrylic polymers imparts both the desired stain resistance and reduced tendency to yellow by standard lightfastness test.
In addition, the (meth)acrylic polymer may comprise residues of other monomers having the vinyl grouping (CH2xe2x95x90CHxe2x80x94). These monomers may be aliphatic vinyl monomers, aromatic vinyl monomers or mixtures thereof.
The preferred weight range of component (a) in the embodiment in which (meth)acrylic copolymer is selected is from 1% to 99% by weight of the total stain resist composition, more preferably from 1 to 66% by weight, even more preferably from 1 to 33% by weight of the total stain resist composition. The preferred weight ratio of the (meth)acrylic polymer to the polyester is from 1:1 to 1:6, by weight.
In addition to components (a) and (b), the stain resist composition may optionally contain etherified phenol formaldehyde condensates and/or acylated phenol-formaldehyde condensates.
In addition to components (a) and (b), the stain resist composition can include other ingredients, such other ingredients include, but are not limited to: water, anionic leveling agents, cross-linking agents, optical brighteners, chelating agents, and inorganic/organic salts, foaming agents, ultra-violet absorption, enhanced lightfastness, etc.
The compositions of the invention may be applied to the substrate in a variety of ways, including but not limited to contacting the substrate in the form of an aqueous medium or a dispersion, such as a foam, and alternatively applying the composition by spray application. Particular methods that may be used include, but are not limited to, Beck dyeing, Continuous Liquid and Foam dyeing, Flood, Flex Nip and Pad applications. The weight ratio of the aqueous medium or dispersion may vary between 0.5% to 500% based on the weight of the substrate. The weight ratio will vary dependent on the manner of application.
The prevailing plant conditions will also affect the amount of treatment composition necessary. The fiber type treated will also influence the application amount. For example, type 6 nylon historically requires application of more treatment composition than type 6.6 nylon.
Application conditions such as pH, temperature, steam and drying time can vary. The pH range for the aqueous medium (including the present composition) used in the contacting step should most effectively be between 0.5 and 10.0 for adequate stain resist. Preferably, the pH range is between 0.5 and 6.0. Most preferably, the pH range will be between 1.0 and 3.5. The temperature at which the fibers are contacted by the aqueous solution may range from ambient to temperatures up to 100xc2x0 C. at atmospheric pressure and above 100xc2x0 C. under pressure conditions (closed atmosphere).
Where production procedures warrant, steam aids in the efficacy of the stain resist product when applied by, but not limited to Beck, Continuous liquid, Flood and Pad applications. The steam time may vary from 15 seconds to 10 minutes, the preferred time being from 2 minutes to 8 minutes. In certain applications but not limited to Flex Nip and Foam Application, drying with forced heat aids in cross-linking and the subsequent fixing of the stain resist material. In one embodiment, the substrate is dried with forced air. In another embodiment, the substrate is dried with microwave heat. The drying time is dependent upon varying conditions predicated by moisture content, range speed, type construction, the weight of the substrate, etc. The drying time may vary from 30 seconds to 15 minutes.
In a preferred embodiment, the application reaction and formulation are performed with the conditions of a pH range of 10 or below, in a temperature range from about 25xc2x0 C. to temperatures at 100xc2x0 C. or above 100xc2x0 C. under pressure conditions and steamed and/or dried for 15 seconds to 10 minutes to impart the desired characteristics and degree of stain resistance.
In another embodiment, the stain resist composition may be contacted or applied to the substrate neat. In yet another embodiment, the stain resist composition may be used to treat the substrate by coextruding the stain resist composition with the substrate. Thus, the stain resist composition can be applied as a post-treatment to the already produced substrate or it can be applied during the process of making the substrate, such as, for example, co-extruding the stain resist with the fiber resin.